Many polymerizable monomeric materials, and particularly vinyl chloride, are being polymerized today on a large scale commercially either in suspension media or in aqueous dispersion or emulsion, i.e., latex form, employing various colloidal suspension agents, emulsifiers or soaps, or synthetic detergent type dispersing agents. In these methods of polymerization, and particularly in suspension polymerization, vigorous agitation is depended upon to suspend and disperse the monomer particles or droplets throughout the reaction media and to maintain such suspension or dispersion during the polymerization reaction and to assist in heat transfer to the reactor cooling surfaces. However, in most instances, polymer particles produced in accordance with these processes are not spherical in shape. Small particles tend to agglomerate into irregular shaped particles. These irregular shaped particles result in a resin with a low bulk density. High bulk density is a desirable polymer property because it gives faster extrusion rates, easier handling and shipping advantages.
Heretofore it has been suggested to use an excess of soap in the reaction medium to overcome agglomeration. This does prevent agglomeration, however, the polymer particles are very small and spherical in shape. Small particles have other processing disadvantages.
It is desirable to produce a polymer having large particle size and the particles be spherical in shape thus giving a high bulk density resin.